Boron triiodide as a micro-crystalline powder was obtained after sublimatio
n of the reaction product of NaBH4 and iodine. An X-ray powder diagram of t
he temperature: air-, and light-sensitive compound was collected at -73 deg
reesC. According to the results of the Rietveld refinement, the crystal str
ucture of BI3 is isotypic to that of BCl3 (space group P6(3)/m, no. 176, a
= 699.09(2), c = 736.42(3) pm). The B-I bond length was determined to be 21
1.2(8) pm.